A STUDY OF THE EGG 327 



6. An egg tester which may be made from a box large 

 enough to hold a small lighted lamp. In the box opposite 

 the lamp cut a hole slightly smaller than the egg. 



Directions. Examine several eggs in the egg tester by 

 holding them in the hole of the egg tester and looking through 

 the egg toward the light. The egg tester must be. used in a 

 darkened room. Observe the size of the air space. The 

 size of the air space gives some indication of the age of the 

 egg. A spoiled egg does not look clear and distinct as a 

 fresh egg does. 



Break a fresh, uncooked egg in a saucer by separating the 

 shell in the middle. Observe the germ on the upper surface 

 of the yolk. Note the chalaza and the transparent watery 

 appearance of the albumen. Examine the shell and observe 

 the air space and the two outer membranes best seen at the 

 air space. Note the pigment of the shell which gives the 

 egg its color. 



Boil an egg hard. Crack the large end of the egg and re- 

 move the shell piece by piece. Observe the air space and the 

 two outer membranes. Cut the egg lengthwise and make a 

 drawing of the longitudinal section showing: 



1. The air space. 



2. The two outer membranes. 



3. The three layers of the white. 



4. The white yolk and the dark yolk. 



5. The germ. 



